The present invention relates to a method of treating psoriasis and/or photo damage in humans with tazarotene in a topical composition from 0.01 to 15% by weight tazarotene, and an alpha or beta-hydroxy acid in a topical composition comprising from 1 to 25% by weight alpha or beta-hydroxy acid. Furthermore, the present invention relates to treating or preventing psoriasis and/or photo damage by topically applying to the skin of a human, tazarotene, such as a gel comprising 0.01% to 0.1%, tazarotene by weight, and an alpha hydroxy acid, such as a cream, comprising 5% to 20% alpha hydroxy acid, e.g. glycolic acid, by weight. The tazarotene topical formulation may be administered once daily in the evening and the alpha hydroxy acid formulation may be administered to the subject once or twice daily in the morning or evening or twice daily in the morning and evening. The tazarotene gel is disclosed in U.S. patent application Ser. No. 623,184, which is entitled xe2x80x9cStable Gel Formulation for Topical Treatment of Skin Conditionsxe2x80x9d, which was filed on Mar. 28, 1996, in the name of Prakash Charu and is hereby incorporated by reference in its entirety. The alpha hydroxy acid cream may be Aqua Glycolic(trademark) Facial Cleanser available from Allergan Herbert comprising 20%, by weight, glycolic acid in a vehicle comprising the following inactive ingredients:
Water, Ammonium Glycolate (and) Glycolic Acid, Cetyl Alcohol, Stearyl Alcohol, Sorbitol, Ammonium Laureth Sulfate, Methyl paraben and Propyl paraben.
The treatment period for psoriasis may be 12 weeks. The subjects are evaluated for lesions with a successful treatment defined as about 50% improvement or better. During the treatment period, tazarotene in combination with the glycolic acid produces significantly better results than treatment with tazarotene in combination with placebo in reducing lesions.